Search

No abstract.

The management of thalassaemia with a severe phenotype includes blood transfusion, iron chelation, bone marrow transplantation, prenatal diagnosis and national programmes to co-ordinate these in countries with a high prevalence. If blood transfusion and iron chelation therapy are not administered regularly, as was the case historically and as is still the case in many poorer regions, progressive deterioration occurs, viz. impaired growth and development, hepatosplenomegaly, bony abnormalities, cardiac failure, increased susceptibility to infections and premature mortality. Remarkable progress has been made in the past few decades, which has led to much-improved survival rates. Transfusion therapy has evolved to a hyper-transfusion regimen designed to maintain a physiological haemoglobin level and achieve a post-transfusion haemoglobin of 14 g/dL, which, as a matter of course, necessitated intensification of iron chelation. The development of effective oral iron chelators has led to improved compliance. Exploration of novel therapeutic approaches continues, with several agents under study. The prospect of gene therapy is particularly exciting as it has potential to provide cure on a large scale. Currently, regular blood transfusion and iron chelation therapy remain the cornerstone of management of thalassaemia major.

Anaemia is defined as a condition in which the number of red cells or their oxygen-carrying capacity is insufficient to meet physiological needs. It is the most common disorder globally and one of the conditions that general practitioners most frequently encounter. In the World Health Organization global database, anaemia is estimated to affect 1.6 billion people. Anaemia may result from (i) decreased bone marrow output; or (ii) peripheral loss, destruction or sequestration of red cells. As anaemia manifests in a whole range of conditions, it is important to embrace a structured diagnostic approach. The recommended approach incorporates clinical and pathophysiological considerations, red cell characteristics, and bone marrow activity. Causes of anaemia related to decreased bone marrow output have been discussed in the previous issue of SAMJ, in the first part of this two-part series. The focus of the current article is on peripheral causes of anaemia.

Thromboembolic conditions are a leading cause of mortality, estimated to account for 1 in 4 deaths worldwide in 2010. Over time, the incidence and mortality rates of these conditions have declined in developed countries, but are increasing in developing countries. A delicate balance exists between procoagulant and anticoagulant factors within the vascular system. Numerous acquired or inherited conditions may tip the balance either way, i.e. towards a prothrombotic or prohaemorrhagic state. Acquired thrombotic disorders are the subject of discussion in this issue, the second of a 2-part series on thrombophilia.

Bleeding disorders (part 2)

No Abstract.

Abnormal bleeding is a common clinical presentation in general practice, and a rational approach to this problem is therefore required. Investigation of a suspected bleeding disorder necessitates a comprehensive history, thorough physical examination and systematic laboratory work-up. Inherited bleeding disorders (IBDs) typically manifest in childhood, but may present later in life after a haemostatic challenge (such as trauma, surgery, tooth extraction). This two-part CME series is intended to provide insight to the medical practitioner on the clinical spectrum, diagnosis and management of bleeding disorders. Bleeding due to inherited disorders is the subject of discussion in part 1 (current issue), and in part 2 (forthcoming issue) the focus is on bleeding from acquired causes. Patients diagnosed with an IBD should ideally be referred to a dedicated tertiary healthcare facility, e.g. haemophilia centre, for management and follow-up.

Background. Retinopathy of prematurity (ROP) is a vasoproliferative disease affecting premature babies and a major cause of blindness in childhood. Appropriate screening and treatment can prevent blindness. Objective. To report on the efficacy of using antivascular endothelial growth factor (bevacizumab) as first-line therapy in ROP. Methods. This was a retrospective analysis of patients with ROP treated at St John Eye Hospital, Johannesburg, South Africa, over a 3-year period. Outcome measures were the clinical response to intravitreal bevacizumab (IVB) as well as the economic impact of IVB therapy. Results. Twenty-three patients were treated for active ROP or type 1 disease, in 44 eyes. Two patients required treatment in one eye only. The mean birth weight of these patients was 1 074 g (range 810 - 1 480). Response to treatment outcome was available for 22 patients (43 eyes). The mean follow-up period was 9 months (range 1 - 18). Forty-one eyes (95.3%) showed complete regression or non-progression of the disease. Two eyes (one eye each in two patients) progressed to advanced disease. There were no short-term adverse events. A cost-effective model showed that IVB treatment was much more economical than laser therapy. Conclusion. IVB is a safe and effective first-line treatment for ROP and should be considered in resource-limited centres.

No Abstract

BACKGROUND: Red cell microcytosis is a common abnormality detected in a full blood count, which often prompts clinicians to investigate further for a cause. In the absence of iron deficiency and anaemia of chronic disease, the differential diagnosis includes β-thalassaemia trait and α-thalassaemia trait. METHODS: We investigated the contribution of α-thalassaemia trait in South African subjects with unexplained microcytosis. Iron studies, haemoglobin subfractionation and multiplex polymerase chain reaction (PCR) analysis for α-globin gene deletions were performed on 97 controls and 86 patients. RESULTS: After excluding iron deficiency, anaemia of chronic disease and β-thalassaemia trait, 78.0% of subjects with unexplained microcytosis were confirmed on PCR analysis to have α-thalassaemia trait. CONCLUSION: Alpha-thalassaemia trait accounts for the majority of unexplained microcytosis.

Bleeding disorders are divided into two broad categories, i.e. inherited, discussed in part 1 of this CME series, and acquired, which is the subject of discussion in the current issue. In contrast to inherited haemorrhagic disorders, where generally a single haemostatic abnormality is found, multiple haemostatic defects are commonly present in acquired haemorrhagic diseases. Bleeding is often a presenting manifestation of systemic disease and requires a multidisciplinary team approach. Iatrogenic causes of abnormal haemostasis are of particular importance to the emergency physician. This CME article aims to provide an approach to the diagnosis and management of acquired bleeding disorders encountered in general practice.

Background. Tuberculosis (TB) remains a global health problem. According to the 2013 Global Report on Tuberculosis, 8.6 million people developed TB in 2012 and 1.3 million died from the disease. An estimated 13% of people who developed TB in 2012 were HIV-positive, and 75% of these lived in Africa. While pulmonary TB is the commonest form of Mycobacterium tuberculosis infection, extrapulmonary TB is increasingly being detected in HIV-positive patients. Definitive diagnosis of disseminated TB is a challenge owing to atypical presentations and diagnostic difficulties (negative chest radiograph and sputum microscopy and culture). A rapid diagnosis of disseminated TB is desirable, as early initiation of treatment can reduce mortality. Although TB culture is the gold standard for diagnosis of TB, it has a long turnaround time (up to 6 weeks). Objectives. To identify a potentially faster and more effective diagnostic strategy for disseminated TB. Methods. A retrospective 18-month review, conducted at a tertiary hospital, comparing histological findings of an auramine O-stained bone marrow aspiration (BMA) smear and a bone marrow trephine (BMT) biopsy specimen with the gold standard of TB culture. Results. Microscopic examination of BMA smears and BMT biopsy specimens offers a rapid diagnostic strategy, with results available on the same day for the former and within 4 days for the latter. BMT histological examination had a significantly higher detection rate than BMA auramine O staining compared with TB culture. Conclusion. We recommend that BMT biopsies remain an essential part of the diagnostic work-up for disseminated TB.

Background: Causes of thrombocytopenia range from laboratory errors to life-threatening pathological conditions. To establish the cause, appropriate laboratory investigation is required.Objectives: To determine the prevalence and causes of platelet counts 20% of the recognised causes). Spurious thrombocytopenia, disseminated tuberculosis, aplastic anaemia, immune thrombocytopenia and malignant marrow infiltration each accounted for 5 - 10% of the causes, while malaria, thrombotic thrombocytopenic purpura, HIV effect and liver disease were each identified in

Background. The HIV epidemic in South Africa (SA) has had a substantial impact on laboratory services, at least partially owing to the well-described propensity to cytopenias in HIV-positive patients. Objectives. ( i ) To formally gauge the impact of HIV infection on the state sector haematology services in SA by determining the HIV seropositivity rate among full blood counts (FBCs) performed at a large academic state sector laboratory; and ( ii ) to document the prevalence of cytopenias among HIV-positive patients in this setting. Methods. Randomly selected FBCs submitted to the National Health Laboratory Service laboratory at Chris Hani Baragwanath Academic Hospital, Johannesburg, were extracted from the laboratory information system (LIS) and retrospectively reviewed. HIV test results and other pertinent information in the LIS were documented, as was the presence of any cytopenias. Results. HIV status was documented in 561 of 1 006 samples (55.8%), with 307 (54.7%) of these being HIV-positive. Of the HIV-positive patients, 63.2% had one or more cytopenia/s. Anaemia was present in 183/307 (59.6%) of the HIV-positive patients, and was severe (haemoglobin

Anaemia is defined as a condition in which the number of red cells or their oxygen-carrying capacity is insufficient to meet physiological needs. It is the most common disorder globally and one of the conditions that general practitioners most frequently encounter. In the World Health Organization global database, anaemia is estimated to affect 1.6 billion people. As anaemia manifests in a wide range of conditions, it is important to embrace a structured diagnostic approach. The recommended approach set out in this article incorporates clinical and pathophysiological considerations, red cell characteristics, and bone marrow activity. In this issue of CME, the first of two parts on anaemia, the causes of anaemia related specifically to decreased red cell production are discussed.

Background. Red cell microcytosis is a common abnormality detected in a full blood count, which often prompts clinicians to investigate further for a cause. In the absence of iron deficiency and anaemia of chronic disease, the differential diagnosis includes β-thalassaemia trait and α-thalassaemia trait. Methods. We investigated the contribution of α-thalassaemia trait in South African subjects with unexplained microcytosis. Iron studies, haemoglobin subfractionation and multiplex polymerase chain reaction (PCR) analysis for α-globin gene deletions were performed on 97 controls and 86 patients. Results. After excluding iron deficiency, anaemia of chronic disease and β thalassaemia trait, 78.0% of subjects with unexplained microcytosis were confirmed on PCR analysis to have α-thalassaemia trait. Conclusion. Alpha-thalassaemia trait accounts for the majority of unexplained microcytosis.

Causes of thrombocytopenia range from laboratory errors to life-threatening pathological conditions. To establish the cause, appropriate laboratory investigation is required.To determine the prevalence and causes of platelet counts100 × 10(9)/L in state health facilities in Johannesburg, South Africa, as well as the quality of the subsequent laboratory work-up in this setting.Full blood counts (FBCs) performed on 7 randomly selected days at the National Health Laboratory Service laboratory at Chris Hani Baragwanath Academic Hospital were retrospectively reviewed. Samples with platelet counts100 × 109/L were identified, and pertinent information was extracted from the laboratory database.Of 4 456 FBCs included, 381 (8.6%) had a platelet count of100 × 10(9)/L. Thrombocytopenia prevalence rates were high in haematology/oncology wards (34.4%), intensive care units (20.5%) and medical wards (18.7%) and among neonatal inpatients (16.5%), and were lowest in outpatient clinics (1-2%). A cause was apparent in ~60% of patients, the commonest causes being chemotherapy and sepsis (each comprising20% of the recognised causes). Spurious thrombocytopenia, disseminated tuberculosis, aplastic anaemia, immune thrombocytopenia and malignant marrow infiltration each accounted for 5 - 10% of the causes, while malaria, thrombotic thrombocytopenic purpura, HIV effect and liver disease were each identified in5% of cases. HIV status was documented in ~70% of the patients, of whom ~50% tested positive. The quality of the laboratory work-up showed differences between specialties within the hospital setting, and was poorest in the primary healthcare clinic sector.Thrombocytopenia is common in hospitalised patients in the Johannesburg academic state sector. Differences in the quality of the laboratory work-up emphasise the need for a standardised approach to thrombocytopenia investigation and increased awareness among clinicians.